The present invention relates to a sheet-processing apparatus, which comprises a convey means for conveying a plurality of supplied sheets one by one and an optical detecting means for optically detecting the sheets conveyed by the convey means, and which processes, in a predetermined way, the sheets being conveyed by the convey means.
An apparatus for sorting bank notes is well known as one type of the sheet-processing apparatus described above. In a note-sorting apparatus, when a bundle of notes of different is supplied to the inlet of a convey means, the convey means takes in the notes from the bundle one by one, and conveys the bank notes one by one. A device for discriminating paper bills is provided at a midway portion along the convey path of the convey means. A portion of the convey path located downstream the discriminating device is divided into branches corresponding in number to the denominations of the bank notes which can be discriminated by the discriminating means. A sorting gate member is provided at the inlet of each of the plurality of branch convey paths so as to selectively guide the bank note conveyed in the convey means into the inlet. A note stocker is provided at an end of each of the plurality of branch convey paths and stocks the bank note conveyed along the branch convey path. The discriminating device discriminates the denomination and authenticity of bank note conveyed along the convey path one by one and actuates the sorting gate member of a branch convey path corresponding to the discriminated denomination of the note. As a result, the note discriminated by the discriminating means is guided into a branch convey path corresponding to its denomination.
More specifically, in the bill-sorting apparatus described above, when a bundle of bank notes of different of denominations is supplied to the inlet of the convey means, the notes of different denominations are sorted in units of denominations and are stocked in the bill stockers corresponding to the denominations.
This conventional note-sorting apparatus has a plurality of optical detecting means for optically detecting a sheet conveyed in the convey means. An optical detecting means is used to detect a jamming of the notes in the convey means, and a timing of opening the isolating gate member of a branch convey path corresponding to the discriminated denomination, in order to correctly guide the bank note, immediately after being discharged from the discriminating device, to the corresponding branch convey path.
Bank note supplied to the bill-sorting apparatus absorb dust or dust attach to the bank note while these notes are ued by people. Therefore, when a large number of notes are conveyed in the convey means, they scatter much dust. Dust is also produced by an abrasion of a bank note resulting from friction between the note and the convey means. The dust attaches to the light-emitting and light-receiving portions of the optical detecting means and causes a trouble of the optical detecting means or, in the worst case, stops the optical detecting means. In order to prevent such trouble in the optical detecting means, an operator of the note-sorting apparatus periodically cleans the optical detecting means. However, in order to miniaturize the note-sorting apparatus, various types of components, including the convey means, the branch convey paths, the note-discriminating device, and the optical detecting means, all of which are described above, are arranged in the housing of apparatus at a high density. Hence, cleaning of the optical detecting means by the operator is cumbersome and requires much time.